Compound gravity pressure tank



Aug. 10, 1954 c. ARNE COMPOUND GRAVITY PRESSURE TANK Filed Mafch 12, 1949 Patented Aug. 10, 1954 .coMeoUnn GRAVITY PRESSURE TANK "Christian Arne, Chicago, 111., assignor "to Chicago Bridge *8: Iron Company, a corporation ofIllinois I Application March 12, 1949, Serial No. 81,032

invention relates to liquid storage systems and-more particularly tocompound gravity pressure systems'for liquid storage tanks.

Liquid storage tanks, particularly water storage tanks, areoiten elevated in order toprovide pressure throughout the supply system. Disregar'ding friction, whichis a negligiblev factor .in theiordinary s'torageftank, the pressure generated byithe tank is afunc'tion of 'thehyd'rostatic head of liquid in the tank and inther'iser connecting the tank withthe system. .I'hus,,in the ordinary construction it is necessary to doubl'ethe height of the tank if twice the pressure is desired. Ob-

viously, there is apractical limit to the extent to which water tanks may be'elevated in order to increase the pressure inthesystemand therefore if further pressureis desired it has been the .customto supplementv th .pressure generated by gravity, that is, the hydrostatic pressure, by means ofauxiliary devices such as-pumps andthe like.

I have invented andam herein disclosing and claiminga compound gravity pressure tank by ,means of 'hich the hydrostaticipressure developed by a series of elevatedtanks mayfbeaccu- ,mulatedso as to generate a finalpressureequal to that which would be generated by a single tank having an elevation equal to the sum of the elevations of each tank.

The invention will be described in conjunction with the accompanying drawings in which:

Fig. 1 is a vertical section through a series of elevated pressure tanks illustrating the principle of the invention; 8

Fig. 2 is a side elevation of a specific example of a compound gravity pressure tank embodying the invention;

Fig. 3 is atop plan view of the apparatus of Fig. 2; and

Fig. 4 is a vertical section throughthe compound gravity tank of Fig. 2.

Referring now to Fig. 1, I show a plurality of elevated tanks H), II, l2 and I3. Tank Ill may be open at its top, if desired, while tanks II, l2 and I3 should be sealed, thatis, should be closed vessels except for such openings as may be necessary to carry out the invention as will hereinafter be described.

A riser l4 connects the container and extends liquid in the container. The container. I5 is sealed except for a header ll which opens to the tank ID with a sealed below the level iii of container above the level of the liquid and con nects the container to the top of the tank II; The pressure generated by the liquid at the tank liquid in connects the space above I0 and riser I4 is thustransmitted by air in the container [5 and header I! to tank I I. Tank II is connected by means of a riser 18 to a second container 19, the riser extending into the .container I9 and below the level 26 of liquidtherein. A second header 2| connects the space above .the liquid in the'container I9 with the to of tank l2 thereby subjecting the tank 12 to the pressure generated by the liquid in the tank 11 'and'riser J13 plus the pressure transmitted'to 'the 'tank I! through the header l I. The tank I2 is connected by means ofa riser22 to a third sealed container 23 and the riser 22 extends below the level 24 of the container 23. A third header '25 the level "of the liquid in the container 23 withthe-top of tank 13. A riser 26 establishes the connection between the ftank l3 and the outlet 21 forthe systemwhich outlet may beusedto fill the-system atthe start.

The pressure at the :outlet is equal to the sum of "the hydrostatic pressures generated by each of the tanks 10,, l2 and 13 and therisers asso- .ciated therewith, and is substantially equal to thejpre'ssure that would be generated by a single tankand, riser elevated above the outlet a distance equal to the sum of the elevationsof each of the tanksin the'system.

A specific form of the invention is shown in Figs. 2, 3 and 4 in which upper spherical tanks 33 and 3! are supported by tubular columns 32, 33, 34 and 35 above the ground 36 and above a lower spherical tank 31. The upper tank 30 is pro vided. with an air vent 41. All of the tanks contain liquid, the liquid level in the uppermost tank 30 being designated by the reference numeral 3 8,

that in the next uppermost tank by the reference numeral 39, and theliquid level in the lowermost tank being designated by the numeral 40. The supporting column 32 is connected to an opening 4| in the tank 3!] which in turn is connected to a pipe Ma extending therefrom to a point beneath the level 38. The column 32 also connects with the lower tank 31 through an'opening 42 therein, from which opening a pipe 42a extends downwardly into the liquid therein. The

column 33 is connected with the interior of the tank 37 above the liquid level by means of an opening 43 and is also connected to the tank 3| through an opening 44 therein. By virtue of the apparatus so far described, the pressure generated by liquid within the tank 30 and supporting column 32 is transmitted to the tank 31 and V thence through air in the column 33 to the tank 3 l. The tank 3| is provided with an open ended pipe 45a extending upwardly from beneath the liquid level and connected to an outlet 45 opening into supporting column 34 which, in turn, is connected to an outlet 46 for the pressure system. Outlet 46 may be used to fill the tanks at the start. The water supply in the tank 3| may be replenished by a supply line within the column 35 and may be pumped thereinto by means of a high pressure pump. The liquid withinv the tanks 30 and 31 is employed only in the pressure generating system and does not under normal operation reach the tank 3! or the outlet 46.

In the specific example of the invention shown in Fig. 2, the pressure generated at the outlet 46 is substantially equal to the pressure which would be generated by a single tank elevated to a position approximately double the height of the mean elevation of tanks 30 and 3|.

While I have shown and described certain embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims.

I claim:

1. A water supply system comprising three sealed tanks having their centers lying in a single vertical plane and each of said tanks containing water, a plurality of columns for supporting the tanks, one of said columns acting as a riser and connecting the water in the lowest tank with the water in one of the upper tanks, another of said columns connecting the space above the water in the lowest tank with the other upper tank, and

a third of said columns acting as a riser for said other upper tank.

2. A water supply system comprising three sealed spherical tanks having their centers lying in a single vertical plane and each of said tanks containing water, a plurality of tubular columns for supporting the tanks, one of said columns being provided with a passage connected at one end to one of the upper tanks and its other end to the lower tank said connection being below the level of water in each of said tanks, another of said columns having a passage connected at one end to the space above the water in the lowest tank and connected at the other end to the other upper tank, and a third of said columns acting as a riser for said other upper tank.

3. A water supply system comprising three tanks having their centers lying in a single vertical plane and each of said tanks containing Water, a plurality of columns for supporting the tanks, one of the upper tanks being open to atmosphere and the other tanks being sealed, one of said columns acting as a riser and connecting the water in the upper open tank to the lowest tank below the water level therein, another of said columns connecting the space above the waterin the lowest tank with the sealed upper tank, and a third of said columns acting as a riser for said sealed upper tank.

4. A water supply system comprising three spherical tanks having their centers lying in a single vertical plane and each of said tanks containing water, one upper tank being open to atmosphere and the other tanks being sealed, a plurality of tubular columns for supporting the tanks, one of said columns being provided with a passage connected at one end to the upper open tank and at its other end to the lower tank said connection being below the level of water in each of said tanks, another of said columns having a passage connected at one end to the space above the water in the lowest tank and connected at the other end to the sealed upper tank, and a third of said columns acting as a riser for said sealed upper tank.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 745,589 Fraley Dec. 1, 1903 746,318 Fraley Dec. 8, 1903 746,488 Fraley Dec. 8, 1903 923,879 Neugebauer June 8, 1909 1,612,017 Hastings Dec. 28, 1916 1,674,341 Penn June 19, 1928 1,755,218 J-ertberg Apr. 22, 1930 2,319,554 Penn May 18, 1943 

